Author Topic: 1986 mercury 115 brown cowl tower of power  (Read 7936 times)

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Offline kegga

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1986 mercury 115 brown cowl tower of power
« on: August 09, 2012, 07:30:39 PM »
Hung this engine on a 1975 gt-150  my question on this engine is  what is  the redline? And secondly  is it wise to run Theese rich or stick with a 50:1 ratio any other advice on this  engine would be helpful. Kegga Worcester mass. Thanks

Offline Hyperacme

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #1 on: August 09, 2012, 07:46:44 PM »
I always mixed mine as close to 50 to 1 as possable  ...  5.9 gals gas to 1 pint of oil.  I had 6 gal. tanks

Think max is 5500 rpm's ...

Offline David CVX-16

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #2 on: August 09, 2012, 08:29:57 PM »
The redline is 5,500 RPM. I mix one pint of oil to 5.75 gallons of gas (about 46 to 1).
David
87' CVX-16, 85' 115 HP Johnson, 58.8 MPH GPS w/ 23" SRX Prop

Offline not2worried

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Re: Re: 1986 mercury 115 brown cowl tower of power
« Reply #3 on: August 10, 2012, 08:49:24 AM »
50:1 should be good. Make sure you using a higher octane, 91 non oxygenated.
1985 SSV 167    THE MARSHMALLOW
115 Hp Merc

Offline bellj

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #4 on: August 10, 2012, 09:07:57 AM »
Curiosity question. Seems to me I've seen it recommended before to use only premium and preferably without ethanol added if you can find it for these engines. I have an '86 V-6 200 that seems to run fine on regular and the manual says it can run on regular OR premium. If I were going someplace and knew that I wanted the best HP output (speed) no matter what for as long as possible that day, then I would spend the extra for the premium for that outing, but why the extra octane for just normal running around?

I know people maybe only use the premium just for precaution - and most of us have a hard time not wanting to push the speed limits, I certainly do as well and probably push it harder than I should - but thought I'd ask anyway. Have there been any examples of motor damage between the regular vs. premium users? Thanks!   :)
Jim, Patti, & Samantha
'69 Pipestone Princess O/B, '57 Evinrude Lark 35
'77 Glastron GT-150 O/B, '78 Merc 700, "The Puddle Jumper"
'77 Switzer GL-20 O/B, '77 Merc 1750
'86 Glastron CVX-20 O/B, '86 Merc 200, "The WHIZZard of Odds"

Offline Rich_V174SS

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #5 on: August 10, 2012, 09:28:38 AM »
From what I understand more octane doesn't increase power. Higher octane resists the ability to detonate (knocking or pinging) in engines with higher compression.
« Last Edit: August 10, 2012, 09:30:10 AM by Rich_V174SS »
1967 V174 Crestflite SuperSport Modified
1987 Mercruiser 190 3.7LX/Alpha One

1970 V176 Swinger
1983 Mercury 115

Offline not2worried

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Re: Re: Re: 1986 mercury 115 brown cowl tower of power
« Reply #6 on: August 10, 2012, 09:48:29 AM »
From what I understand more octane doesn't increase power. Higher octane resists the ability to detonate (knocking or pinging) in engines with higher compression.

yep, that's why lower octane could damage the motor. As far as ethanol, it can causes carburetor to gum up and its affects some rubber, plastic and aluminum.  I know plenty of people that run regular gas, but will store with non oxy. With my tower of power, I only run higher octane and non oxy.
1985 SSV 167    THE MARSHMALLOW
115 Hp Merc

Offline Jerry

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #7 on: August 10, 2012, 11:42:09 AM »
OK, time for a little "Gasoline 101"
Octane rating is how you measure how fast the mixture burns (controlled explosion) in the cylinder. The higher the octane the slower the explosion. This use to be controlled by an additive from Ethyl Corp that was added to the gas (lead). This stuff like DDT was just bad for everyone. It not only killed brain cells,it caused deposits on valves and rings. That's why motors run 350,000 miles today instead of 100,000 like they did 40 years ago.

Two things control the rate of burn. A lean mixture burns faster than a rich mixture, so you can run less spark advance with a lean mixture. Back in about '62 I asked Don Garlits http://garlits.com/ how a small block chev could ever beat a hemi. "easy, burn more gas". so with a rich mixture you can run more advance. I ran this car normally on hi octane gas and 52 degrease of total advance. It ran 150 MPH, but if I richened it up and ran regular it ran 155 mph. I came off the starting line at 6,000 RPM, and shifted at 10,000 rpm.



Ethanol adds Oxygen to the gas to give a more complete burn, but it can eat older natural rubber parts which we shouldn't have. It also runs leaner, but 10% shouldn't matter in our motors. If you worry check your spark plugs. If they are snow white and have aluminum specks on them put bigger jets in the carb, or back off the timing. I run non-oxygenated premium (Leroy's 90th and Lyndale in Bloomington) and Amsoil at 90 to 1 (1/2 pint to 5 gallons) but I ran regular in a motor with 12 to 1 compression.



Do whatever you're comfortable with.  Back in the 50's they ran "white gas" at 25 to 1 and you couldn't breath for the smoke and there was an oil slick on the water.
'72 Glastron GT160 Sport - Okie-Dokie
'63 Winner - Grandpa's Fisn-Bote
'63 Glasspar SeaFair Sunliner - Mischief Maker

Offline Jason

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #8 on: August 10, 2012, 12:28:35 PM »
just play it say and run non-oxy.

MN is sneaky. WI post's ethanol content on every pump It's not always posted if it's ethanol free or not. MSRP has a list of station's in MN that sell it. Most places on the water are non-oxy too, but ask.

I have heard that ethenol in gas is eating away the metal in carb flote bowls. Also eats old rubber fuel lines and clogs the jets in the carb as seen here:
http://forums.iboats.com/showthread.php?t=330129

Everything I own with a carb gets non-oxy and work great.
« Last Edit: August 10, 2012, 12:32:52 PM by 74GlasCarlSS »
Jason S.
1974 Glastron Carlson CV16SS 140 I/O
1986 Glastron Carlson CV23 260 I/O

Offline badgercarlson

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #9 on: August 10, 2012, 12:52:06 PM »
I agree. I run everything (1977 Merc 1150, lawn mower, snowblower, leaf blower) with non-ethanol premium.

Offline Jerry

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Re: 1986 mercury 115 brown cowl tower of power
« Reply #10 on: August 10, 2012, 02:22:35 PM »
A little long, but a good story.

For years our old next-door neighbors, Thurman and Diane Taylor, and us were planning on a trip to the Black Hills. They moved to Indianapolis, but we would meet somewhere to vacation together. This was the year for Deadwood. We met them at a nice campground in Salem SD Thursday night. After supper we sat around the campfire and talked till midnight. Friday morning we left for the 400-mile trip to Deadwood. First stop was Mitchell and the Corn Palace.



After taking all the tourist pictures, we filled both motorhomes with gas.  Now I have deep respect for Corn Farmers, and I certainly believe in clean air, but don’t ever put ethanol in an older vehicle when it’s hot out. Ethanol boils at a much lower temperature than gas.  As we were pulling out of Mitchell on I90 Thurman radioed me that he couldn’t go over 55 MPH. I slowed down, and we kept on turckin. Everything was fine till we crossed the Missouri River. Pulling the grade in 100-degree heat was too much for my rig. I started cutting out. We limped from one peek to the next, and finally pulled off, and tried to wash out the radiator so it would cool better. I thought we had it solved then at Vivian, in the middle of nowhere, it gave up.  We sat at Vivian SD for eight hours in 118-degree heat until almost 9 o’clock. With the temperature down to 95 we thought we could make it. The locals just laughed and said “oh ya don’t ever run Ethanol in the summer”. They also said to add a gallon of Diesel fuel to the gas, so we filled both rigs with real gas, and I added a gallon of Diesel, and off we went.
We pulled into Deadwood about 12:30 AM. Our reservations had been canceled at the Deadwood KOA because we didn’t know when we would get there, and if we didn’t cancel we would get charged. We ended up in the Public lot that said “NO OVERNIGHT CAMPING” after explaining our woes to the local officer. We took a tour of Main Street and had a “Midnight Snack”, went back to our Motorhomes and slept till nine.  We couldn’t get to our campsites until 11 o’clock, so we did some shopping and lost a couple bucks in the “Bandits” before going to the KOA.
After getting hooked up, and the air-conditioning turned on, we set out for Mt. Rushmore. Thurman and Diane towed their car with them so we had a way to get around. We saw the rock-group, and Custer State Park, and then headed for home.



As we got close to Deadwood there was a roadblock set up. The Sheriff asked where we were going?  “Dead wood” we said, “no you’re not” was the reply. There was a major forest-fire within feet of Deadwood. Everyone had been evacuated. He suggested we go to Rapid City and find a Motel.  There wasn’t a motel room within a hundred miles of Rapid City. We had found a radio station from the Deadwood/Lead area that had all the details of the fire. They kept saying to go to the evacuation center at the Young Center at the Black Hills State Collage in Spearfish, so that’s what we did. The Red Cross had a Doctor there that wrote some prescriptions for Diane (all her medication was in their motorhome.)  The Salvation Army had brought in some pizza and Burger King. We had some supper, got a couple cots, and settled in for the night.  By morning the National Guard had taken control of the Disaster Relief Center, and “Chow” was served in the cafeteria. It was very good and more than we could eat. I tried to find out from the Guard if our campsite was safe. After calling the Sheriff’s office they told us it was OK, and we could get within two blocks of it. If we were there they might let us in to get our motorhomes and get out of town. When we got to the roadblock the Highway patrol was there. We told him of our plight, and asked if we could get in. He told us to go just to the KOA and no further. We did.



The trip home was great, even in 90-degree heat. The old motorhome ran great. I think it was afraid we would take it back there.
'72 Glastron GT160 Sport - Okie-Dokie
'63 Winner - Grandpa's Fisn-Bote
'63 Glasspar SeaFair Sunliner - Mischief Maker